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I-35W Bridge Collapse

I-35W Bridge Collapse. Dan Dorgan Presentation to SCOH Annual Meeting. I-35W Bridge History. Construction started in 1964 Opened to traffic in 1967 Steel truss deck, 113 feet, 4 inches wide 64 feet high, 1,907 feet long, 14 spans Four lanes of traffic in each direction

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I-35W Bridge Collapse

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  1. I-35W Bridge Collapse Dan Dorgan Presentation to SCOH Annual Meeting

  2. I-35W Bridge History • Construction started in 1964 • Opened to traffic in 1967 • Steel truss deck, 113 feet, 4 inches wide • 64 feet high, 1,907 feet long, 14 spans • Four lanes of traffic in each direction • Carried 140,000 vehicles daily, including 5,700 commercial vehicles • $440,740 to construct the piers • $4,823,262 to construct the bridge • Scheduled for reconstruction in 2020-25

  3. I-35W Bridge - Looking North July, 1967

  4. Bridge Rating • Inspected annually since 1993; before that, was inspected every two years • Superstructure rated “structurally deficient” in 1990 • This was due to: • Corrosion where the paint had deteriorated • Poor weld details in the steel truss members and floor beams • Bearings that were not moving as they were designed to move • Existing fatigue crack repairs to the approach span beams

  5. Maintenance Work at Time of Collapse • Replace concrete overlay, repair joints and lighting, and install guardrail • Work completed on outside two lanes each direction • Scheduled completion date - September 30, 2007 • Cost - $9 million • Contractor employees and Mn/DOT inspectors on bridge at collapse

  6. The Collapse • Occurs at 6:05 p.m. Wednesday, August 1, 2007 • Over 100 vehicles were on the bridge at time of collapse • 13 fatalities • 105 injuries

  7. Corps of Engineers video

  8. The Response The First 24 Hours

  9. Mn/DOT’s Regional Transportation Management Center (RTMC) Mn/DOT’s Immediate Response • 6:05 p.m. - Numerous concurrent calls to State Patrol Dispatch (911) and from field employees to RTMC and Maintenance Dispatch • 6:10 p.m. - District Emergency Operations Center activated and DEOC staff report to RTMC • Immediate traffic control for ramp and freeway closures provided by FIRST units, maintenance units, and contractors in the vicinity

  10. Statewide Incident Response • 6:20 p.m. – State Emergency Operations Center and Joint Information Center activated. • Unified command center set up on collapse site. Authority in command changed as incident progressed: • Mpls. Fire Department in charge of rescue • Hennepin County Sheriff in charge of recovery (Mn/DOT assisted with some demolition) • Mn/DOT assumed command after recovery was completed

  11. Emergency Service Response • Mn/DOT Metro district provides maintenance staff and equipment • Mn/DOT structural engineers called to site • Effective response due to communications, planning, equipment, training, and experience with incidents on the Metro area freeway system

  12. Traffic Response • 6:20 p.m. - began converting temporary traffic control measures to more long term traffic control standards. • 20 changeable message signs activated • Mn/DOT assisted state patrol and other enforcement personnel • Instituted 24-hour staffed traffic control • By 7 p.m. – Over 150 employees activated • 11:00 p.m. - Detour maps for a.m. rush posted on Mn/DOT Web site • Overnight – closed I-35W with temporary barricades and converted Hwy 280 to a freeway.

  13. Public and Media Response • 6:10 to 8 p.m. continuous Mn/DOT traffic radio coverage • Detour maps and info provided on Web and 511 Traveler Information • Media briefings, interviews • Coordinated responses with other agencies/governor’s office http://www.511mn.org http://www.dot.state.mn.us/i35wbridge/index.html

  14. Security Response • Mn/DOT safety officers statewide called in • Homeland Security & FBI investigate criminal or terrorism potential • OSHA ensures safety • Navy divers assist recovery • U.S. Secret Service for president visit • No-fly zone activated

  15. Internal Agency Response • Employees knew what to do, when to go, who to report to • Aug. 2 – Lt. Gov. e-mail to employees • Aug. 2 – State employee assistance available • Aug. 6 – Lt. Gov./Deputy thank employees • Aug. 8 – Tips to employees on handling threats • Critical incident stress debriefings provided

  16. The Response Local and National

  17. Governor’s Response • Aug. 2 - Governor Tim Pawlenty declares a state of emergency and activates State Emergency Operations Center

  18. U.S. DOT Response • Aug. 2 – U.S. DOT Secretary tours site and announces $5 million grant to help pay for early expenses

  19. Executive Branch Response • Aug. 3 - First Lady Laura Bush visits the site, victims families • Aug. 4 - President Bush pledges to cut red tape that could delay recovery • Aug. 21 - President declares emergency under Robert T. Stafford Act authorizing funds for safety and recovery efforts President Bush participates in a briefing with Minneapolis Mayor R.T. Rybak and Gov. Tim Pawlenty

  20. Congressional Response • Congress authorizes $250 million in Emergency Relief money to repair and restore highway facilities to pre-disaster conditions

  21. Mn/DOT’s Continuing Response • Investigation • Inspections • Traffic Recovery • Bridge Demolition • Bridge Replacement • Media/Public Responses

  22. Continuing Response Investigation

  23. The Search for a Cause • Cause may not be known for 12-14 months

  24. The Search for a Cause • National Transportation Safety Board leads investigation • Forensic engineering firm assisting investigation • Consultant to review inspection procedures

  25. Continuing Response Inspection

  26. Inspection • Aug. 2 - Governor directs Mn/DOT to inspect all bridges on the trunk highway system in priority order • Aug. 6 – Mn/DOT completes inspection of five bridges with the same arch deck truss design as I-35W bridge • Inspection continues of state bridges, structurally deficient and fracture critical bridges priority • Aug. 10 – Mn/DOT requests that local agencies and private owners accelerate inspections of their bridges • Dec. 1 - Mn/DOT’s goal to complete all state bridges inspections

  27. Inspection • Approximately 13,600 > 20 ft. long bridges in Minnesota - 3,800 TH, 9,800 local • 197 fracture critical bridges in Minnesota – 72 TH and 125 local • 34 pin assembly bridges - 15 TH and 19 Local • 1,111 structurally deficient bridges – 106 TH and 1,005 local

  28. Continuing Response Traffic Recovery

  29. Traffic Restoration • Work to convert Hwy 280 to a freeway including closing at-grade signalized intersections to cross traffic, upgrading ramp termini signal systems and lengthening frontage road • Add lane each direction on I-94 from Hwy 280 to I-35W by overlaying and restriping shoulders • Many temporary projects on other Metro alternate routes

  30. Traffic Distribution After Collapse

  31. Transit • Metro Transit assigned 25 extra buses, ridership jumps 25-50% • Advised public to “buy bus passes, stagger work hours, carpool” • Began studying additional service enhancements Park-and-Ride use jumps after I-35W bridge collapse

  32. Continuing Response Bridge Demolition

  33. Bridge Demolition and Removal • Aug. 6 – demolition begins to aid recovery, Carl Bolander & Sons Co., awarded demolition contract • Aug. 20 – recovery completed, site turned over to Mn/DOT • Sept. 6 - Navigation channel opened to commercial traffic

  34. Bridge Demolition and Removal • As of Sept. 26: • Steel removed from river • Corps will sweep channel • Restrictions still on recreational river traffic • Some demolition will continue after Oct. 15 • NTSB on site through end of year

  35. Continuing Response Bridge Rebuild

  36. Bridge Rebuild • 189’ wide • 10 lanes of traffic, five in each direction • Designed to handle Bus Rapid Transit (BRT) and/or a managed lane (like I-394 MnPASS) • Designed to be LRT ready

  37. Bridge Rebuild – Design Build • Aug. 4 – Design Build teams pre-qualified • Aug. 14 – public involvement process begins • Aug. 21 – layout submitted to Minneapolis • Aug. 23 - RFP delivered to five design-build teams • Aug. 23 – all but 3 environmental permits acquired • Sept. 19 – project bid letting • Oct. 15 - work scheduled to begin • Dec. 2008 – projected bridge completion date

  38. Bridge Rebuild - Review Process • Minneapolis Municipal Consent hearing Sept. 20 • Technical Review Committee reviewed proposed design • Visual Quality Advisory Committee met with Design-Build teams

  39. Bridge Rebuild-Stakeholder Involvement • Six open houses • Community group Meetings • Presentations/listening sessions • Meetings with local, state, federal officials • E-mail alerts/ notifications • Web site, online comment form • Handouts at park-and-ride lots

  40. Responding to What We Heard • Build bridge to accommodate future LRT • Build a quality, attractive bridge we can be proud of • Mitigate construction impacts • Maintain key road and bike accesses • Require DBE involvement • Keep us involved!

  41. Bridge Rebuild-Environmental Review • Environmental reviews accelerated due to cooperation among agencies • Includes a thorough analysis of the full range of potential environmental issues for all aspects of the project • Met NEPA requirements

  42. Bridge Rebuild Legislative/Congressional Hearings • Aug. 15 – Hearings with Minnesota House and Senate Transportation Committee • Sept. 5 – Mn/DOT staff testified before the U.S. House of Representatives Committee on Transportation & Infrastructure

  43. Bridge Rebuild - Economic Impacts • Economic factors create urgency to rebuild quickly • Daily costs to motorists of additional travel time and distance estimated at $400,000 • Reduction in state’s average net economic output is an additional $113,000 per day

  44. Continuing Response Media/Web info

  45. Media and Public Response • Media interest worldwide • Media briefings, interviews • Mn/DOT directed to be transparent in info provided • AG’s office required retention of all incident-related data • 50+ data practices requests • Dedicated I-35W Web site includes all documents

  46. Conclusions What Went Right? Lessons Learned?

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